Door closing and locking means for autoclaves and the like



May 12, 1970 A. E. THOMAS ET AL 3,511,593

DOOR CLOSING AND LOCKING MEANS FOR AUTOCLAVES AND THE LIKE Filed May 15,1967 2 Sheets-Sheet 1 R. 0 WM E A WN m M a M 4mm flx fl l w M a 1 w I r-wl ev 1&

May 12, 1970 A. E. THOMAS EI'AL 3,511,593

DOOR CLOSING AND LOCKING MEANS FOR AUTOCLAVES AND THE LIKE Filed May 15,1967 2 Sheets-Sheet 3 INVENTOR. ARTHUR E. THOMAS BY dohw A. ALWAKDUnited States Patent 3,511,593 DOOR CLOSING AND LOCKING MEANS FORAUTOCLAVES AND THE LIKE Arthur E. Thomas and John E. Alward, Erie, Pa.,as-

signors to American Sterilizer Company, Erie, Pa.,

a corporation of Pennsylvania Filed May 15, 1967, Ser. No. 638,513 Int.Cl. B01j 3/00 US. C]. 2193 11 Claims ABSTRACT OF THE DISCLOSURE Doorcontrol and locking means in combination with a pressure vessel orsterilizer having a vertically slidable door movably attached thereto.The pressure vessel includes cam means mounted thereon to force the doorinto seating engagement with said pressure vessel when the door is inthe closed position.

Previous doors adapted for use with sterilizers have been either of amanual type or power operated type. The power operated type have beencomplex and expensive in construction. Manually operated sterilizer doorpresent certain inherent disadvantages, which are well known to thoseskilled in the art.

The door and sterilizer disclosed herein utilizes a simple, positive,and convenient power operated sliding door with sealing and lockingmechanism. The locking mechanism incorporates a top edge and two sideflanges on the door which curve around and form forwardly facing camengaging surfaces. The sterilizer has four shafts disposed along foursides of the door, and each of these shafts has a set of cams to engagethe flanges. These cams may be made up, for example, of a circular diskhaving a keyed hole drilled off center to form an eccentric in thedriving member. A steel rim is provided concentric with the disk to takethe loads imposed by the followers on the doors. An anti-frictionbearing is provided between the rim and the disk. When the cam shaftsrotate, the eccentric rotates and the bearings and rim are broughtcloser to the follower. When the rim contacts the follower, it will stoprotating and transfer the force of the cam to the follower moving itaway from the cam shaft. The sliding action then takes place between therim and bearing or the bearing and the eccentric and, therefore, doesnot wear out the periphery of the rim or the face of the follower.

The doors are equipped with adjustable seals, which make it possible todistribute the sealing force on the door to form an eflicient seal.

It is, accordingly, an object of the invention to provide an improvedcombination sterilizer chamber and sealing means.

Another object of the invention is to provide an improved lockingarrangement for a sterilizer door.

Another object of thet invention is to provide an improved closure,operating mechanism, and sealing mechanism.

Another object of the invention is to provide a door and lockingmechanism, which is simple in construction, economical to manufacture,and simple and efficient to use.

With the above and other objects in view, the present invention consistsof the combination and arrangement of parts hereinafter more fullydescribed, illustrated in the accompanying drawing and more particularlypointed out in the appended claims, it being understood that changes maybe made in the form, size, proportions, and minor details ofconstruction without departing from the spirit or sacrificing any of theadvantages of the invention.

3,511,593 Patented May 12, 1970 In the drawings:

FIG. 1 is an isometric view, partly broken away, to better illustratethe invention;

FIGS. 2, 3, 4, and 5 are cross sectional views taken on cross sectionlines numbered with corresponding numbers in FIG. 1.

Now with more particular reference to the drawings, the autoclave orsterilizer is generally indicated at 10 with the door locking mechanismand sealing arrangement shown by way of example. The sterilizer 10 hasdoors 11 and 11' at opposite ends, and each of these doors has fourshafts 12, 13, 14, and 15 connected together by pinions 17, so that eachshaft is connected by the pinion to the shaft adjacent it. Therefore,the four shafts form what is called in the trade, a four square shaftarrangement.

The cams are each made up of a disk 31, which is fixed to the cam shaft15 and an anti-friction bearing indicated at 32 connects the cam member33- to the shafts. The shafts 15 are journalled in brackets 34, whichare fixed to the sterilizer chamber indicated at 30. The door 11 has afront panel 35 that is spaced from and generally parallel to rear panel37. Panel 35 is formed inwardly at 36 and attached to the rear panel 37of the door, and the lower end of the panel 37 and the downwardlyextending portion 38 form a support member for the cam follower plate39. The cam members 33 bear against the follower plate 39 and urge thelower edge of the door inward. The rear plate of the door has theresilient seal 40 attached to its periphery, and this seal engages thefront surface 41 of the rim 42, which extends around the door opening43. The seal 40 is clamped to the rear plate 37 by means of a clampingring 44. The plate 39 can be adjusted toward and away from the doormember 38 by means of the set screws 45. Thus, the follower plates canbe adjusted to cause the cams to transmit a uniform pressufe to the doorseal and thereby obtain an optimum seal.

The door 11 has plates 46 at the sides which form channels and extendoutwardly at 47, rearwardly at 48, and then extend inwardly behind thecam. The channels receive the cams at the sides of the door when thedoor slides up and down urged by the cylinder 21 which is a part of thelifting mechanism 20. A piston rod 24 is pivoted to the cable 26 at 25and to the frame 22 at 23. The cable 26 passes over the pulleys 27,which are pivoted to the frame at axle 28, and the cables 26 areattached to the door at 29. Thus, when the piston in the cylinder 21 isactuated, it exerts a force on the cable 26 to lift the doors, and whenthe force on the piston is released, the gravity will cause the door tolower.

The cylinders 50 are each pivoted to the frame by pins 51. Each cylinder50 has a piston rod 52, which is connected to a bellcrank 53 at 54. Thebellcranks are fixed to the shafts 13 and 13'. Thus, when the piston incylinders 50 are caused to extend, they rotate the bellcrank 53, andthereby rotate the shafts 13 and 13', which each in turn rotate theshafts connected to them by and through beveled pinions 17. The pinions17 rotate the earns 16 to either a locking position when they exert aforce on the plates 46 and 54 or to a released position when the camsare moved away from the plate 46.

It will be noted that the plate 64 is fastened to the upper edge of thedoor at 55 and it extends upwardly, then rearwardly then downwardly sothat when closed, the plate extends behind the cams 16. Thus, it will beseen that when the door is in the closed position shown, the cams willengage the forwardly facing edge of the plate 64. The cams will likewiseengage the forwardly facing inturned edge of the plates 46. The cams atthe lower edge of the door will engage the forwardly facing lower camfollower plate 39.

The foregoing specification sets forth the invention in its preferredpractical forms but it is understood that the structure shown is capableof modification within a range of equivalents without departing from theinvention which is to be understood is broadly novel as is commensuratewith the appended claims.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. In combination, a door, an autoclave, and a sealing and lockingmechanism,

said autoclave comprising a pressure vessel having an opening,

said door being supported on said autoclave,

means to move said door from a closed position to an open position,

said locking mechanism comprising cams supported on said autoclave,

said door being movable generally in a plane from an open positionrelative to said door to a closed position,

said door having cam means supported on the outer periphery of saiddoor,

said cam means having camming surfaces thereon,

said cams being disposed on the camming surface of said cam means remotefrom the outside surface of said door when said door is in closedposition,

and means to move said cams to force said door into seating engagementwith said autoclave.

2. The combination recited in claim 1 wherein said cam means comprise afirst follower member, a second follower member, a third follower memberand a fourth follower member,

said first follower member being attached to'said door and extendingoutwardly, then rearwardly, then inwardly and having a first forwardlyfacing surface comprising a said camming surface adapted to be engagedby said cams,

said second follower member being attached to said door on a sidethereof opposite said first follower member and extending outwardly,then rearwardly, then inwardly and having a second forwardly facingsurface adapted to be engaged by said cams,

said third follower member being attached to the lower side of said doorbetween said first follower member and said second follower member,

said third follower member being attached to said door and extendingrearwardly, then outwardly, and having a forwardly third facing surfaceadapted to be engaged by said cams.

3. The combination recited in claim 2 wherein said cams are disposed ona first shaft, a second shaft, a third shaft and a fourth shaft,

said first shaft being disposed in front of said first forwardly facingsurface,

said second shaft being disposed in front of said second forwardlyfacing surface,

'said shafts being rotatably connected together to form a square.

4. The combination recited in claim 3 wherein said door moves up anddown,

a bell crank is connected to one said shaft,

and a hydraulic cylinder is attached to said autoclave and a piston insaid cylinder having a piston rod connected to said door.

5. The autoclave recited in claim 2 wherein said follower memberscomprise plates extending from in front of said cams around said cams toa position behind said cams.

6. The autoclave recited in claim 5 wherein a follower plate is attachedto each said member,

and means to adjust said follower plate toward and away from said cams.

7. An autoclave having a door opening at one side,

a door slidable up and down from an open position to a closed positionmovably mounted on said autoclave,

four shafts disposed generally in the form of a square around said door,

gear means connecting the ends of said shafts together,

cams on said shafts,

follower means on said door on the edges thereof extending between saidcams and said autoclave,

and means to rotate said shafts whereby said cams can be moved to forcesaid door into seating engagement with sealing means on said autoclave.

S. The autoclave recited in claim 7 wherein said means to rotate saidshafts comprises a hydraulic cylinder having one end attached to saidautoclave and a piston rod connected to one said shaft.

9. The autoclave recited in claim 8 wherein a second cylinder isconnected to said autoclave with a piston thereon connected to a saidshaft spaced from said shaft con: nected to said first mentioned pistonrod.

10. The auoclave recited in claim 9 wherein said piston rods areconnected to said shafts by means of bellcranks.

11. The autoclave recited in claim 10 wherein said autoclave has asecond door opening on the end thereof opposite said first mentioneddoor opening and a second 'door is supported on said autoclave to openand close said second opening.

References Cited UNITED STATES PATENTS 3,147,068 9/1964 Castle et a1.2198 3,371,986 3/1968 Brown 2198 MORRIS O. WOLK, Primary Examiner B. S.RICHMAN, Assistant Examiner US. Cl. X.R.

